1) Hey have 10 barred roc hens and 1 barred rooster, do u think any of them will ggo broody ths year or any other year. they are born n september. ?

Barred rocks have a reputation of not being a broody breed. For people who made a living based on egg production, broodiness was often a fatal condition, so broodiness has been bred out of them. They don't lay eggs when they are broody. You may get lucky and get a broody. There is no way to tell. It purely depends on luck, but barred rock is not a breed I'd consider likely.

2) is it ok to put silkies wth them?

Yes, you can mix them. You may have problems introducing new chickens of any breed, even the same breed, to any flock, but once you get over that you should not have any problems.

3) my coop is 4x12 and i live n LA so they never are n the coop execpt at nght. My run 25sq feet and they free range most of the week. How many more chickens could fit n there.

As far as your coop goes, if you feed and water outside, their nest boxes are up off the floor or are outside, and they only use the coop for roosting, I'd feel comfortable with another 8 or 10 chickens. You do need to make sure the coop is well-ventilated and the litter stays dry or they can get respiratory problems.

The run is the problem. With only 25 square feet, you have too many chickens now if they spend much time at all locked in there. You are taking a risk that they will get bored and start cannibalizing each other. If they freerange all the time and the run is only where you feed and water, then it won't be a problem. You are probably getting away with it now as they use both the run and coop when they are in there, which means they are using the coop for more than just roosting. In that case, forget what I said about the coop handling more chickens.

4) when will ther eggs get bgger

They should have just started laying, so you migth see a very slight increase in size in the next few weeks, but the eggs will probably not get significantly bigger until after they molt.